It's not compulsion to spend some money and do the course. When i started rails, i was without even computer sciences background. The best way to learn rails is by doing and learning with application development itself. In this regard this may help - http://ruby.railstutorial.org/ruby-on-rails-tutorial-book

Keep in mind, the best way to go with rails is learn the conventions, once you get them you will start loving rails or else thing might frustrate you.